This application claims the priority of Korean Patent Application No. 2004-61957, filed on Aug. 6, 2004 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a camera module applied to a mobile phone or a digital camera, and more particularly, to a lens holder structure of an image sensor camera module and a method of fabricating the same.
2. Description of the Related Art
Use of digital cameras is increasing along with internet video communication and the like. Also, with the increasing popularity of next generation mobile communication, compact camera modules are increasingly required to use compact personal digital assistants (PDAs) in video communication or the like. In other words, there is a greatly increasing demand for subminiature camera modules directly and indirectly related to high- and multi-function digital cameras.
In particular, cameras adapted in mobile phones used for mobile communication employ compact camera modules.
FIG. 1 illustrates a conventional image sensor camera module. Referring to FIG. 1, a barrel 30 in which a lens 80 is mounted is attached to a lens holder 20. The barrel 30 is inserted into the lens holder 20 using a matching threading of the lens holder 20 and the barrel 30. By rotating the threaded barrel 30 within the threaded lens holder 20, a distance between the lens 80 and an image sensor 70 attached on a circuit board 10 is adjustable. This distance is then used to adjust the focus of the lens 80. However, in a case where an axis 60 of the lens 80 does not coincide with a central axis 50 of the image sensor 70, an image with a high resolution cannot be obtained via the lens 80, and the phase of the image is also not clear. Thus, the barrel 30 is necessarily adjusted to allow the axis 60 of the lens 80 to coincide with the central axis 50 of the image sensor 70, i.e., a length distance between the lens 80 and the image sensor 70 is necessarily adjusted.
In other words, the conventional image sensor camera module is completed by separately assembling the lens holder 20 into which the barrel 30 is inserted, and the image sensor 70 is attached on the circuit board 10. Both the accuracy and reliability of the conventional image sensor camera module are poor because the axis 60 of the lens 80 will often not coincide with the central axis 50 of the image sensor 70. Another shortcoming of the conventional image sensor camera module is that the barrel and lens holder threads may cause particles to be generated during a rotation of the barrel 30. The particles may contaminate the image sensor 70, which may affect the operation of the image sensor 70.